India squandered the lead gained through drag-flicker Rupinder Pal Singh in the 23rd minute as Pakistan rallied with penalty corner goals from captain Muhammad Imran and Sohail Abbas in successive minutes midway through the second session.
India enjoyed an edge in the first half but lost the plot after change of ends with Asian Games gold-medallist Pakistan turning the tide in their favour by dominating the entire second session.
Arjun Halappa-led side were unlucky as the referee disallowed a goal early in the match. They also wasted a few open chances in the first session which could have changed the complexion of the game.
The loss also snapped India's four-match winning streak against Pakistan since last year.
With the loss today, India, outright winners in 2009 and joint champions with South Korea in 2010, slipped to the fourth spot in the round-robin league standings with seven points from five matches. Pakistan moved up to the third place with nine points in five games.
World champions Australia are leading the standings after their 4-2 victory over South Korea today to secure to 10 points in four matches, while Britain are second on nine points from four outings.
India have one match remaining -- against New Zealand tomorrow, in the round robin league.
Each side play six matches in the seven-team competition. The top two sides in the standings after the round-robin league will play in the summit clash on May 15.
India had the first shy at the Pakistan goal in the eight minute when Vikas Pillay moved forward on the left flank and sent a diagonal cross to which Mandeep Antil failed to connect in the goalmouth.
The Indians almost took the lead in the 14th minute on their first penalty corner but as Dhananjay Mahadik's shot was blocked by the goalkeeper, but Shivendra Singh sent a stinging reverse from the top of the circle to hit into the boards.
Dutch umpire Roderick Wijsmuller first signaled for a goal, but changed the decision after Pakistan team protested for an obstruction.
Gurvinder Singh Chandi missed a sitter in the 20th minute when he failed to push in S V Sunil's pass into an open goal, but penalty corner shooter Rupinder Singh put India ahead in the 23rd minute by sending a deft drag-flick into the cage.
